Who knew there were so many gentlemen in the 21st century? The Chap Olympiad in Bloomsbury has been selling out for five years, with refined ladies and gents lining up to joust with umbrellas, hurl cucumber sandwiches on china-plate discus, play tug-o-war with a gigantic handlebar moustache, and surf to the finish-line on ironing boards carried by housemaids and butlers - all without letting the pipe slip from their lips.

And the Chap Olympiad in the Olympic Park (and, in September, at Goodwood Revival) promises silliness on a scale that is grander still, with music and performances as well as wacky races. Come in vintage, come in tweed, come in your best sports sock-suspenders.

Chap Olympiad in the Olympic Park runs 29 July and 3-4 August; and at Goodwood Revival 14-16 September 2012. For more details or to book tickets, contact www.thechapolympiad.com

Table tennis has several advantages over tennis. You don't have to run around much, you don't need much space, and you can play it with a Pimm's in one hand. All of which makes it an ideal sport for all ages to play at venues around the capital, from libraries and nightclubs.

Formerly a parlour game known as wiff-waff, table tennis became an Olympic sport in 1988. And, like synchronised swimming, it is enjoying something of a recent resurgence. Tables are popping up in parks, shopping centres and markets right across London, as well as Liverpool and Bristol, again this summer. They are free to use and even come with bats and balls, so you can turn up whenever you like for a knockabout.

The Social Athletics Club will be bringing an element of organisation to London's squares throughout July, with their pop-up tournament 'Smash the City'. These, too, are free; sign up and bring your best doubles partner, or turn up and take pot luck. The grand final is at midday in Exchange Square.

It is not just for the young, as the excellent documentary Ping Pong shows. It's the slightly batty journey following several OAPs from all over the world - including a 100-year-old Australian great-grandmother - to China, on their quest to win gold at the world championships. They may not be fast on their feet, but their backspin is still something to behold. The film is part of the Cultural Olympiad, touring the country this summer.

Olympic table tennis takes place at ExCel this summer. For more details and table locations of free tables around the city, visit Ping!. For dates and locations of 'Smash the City' contact the Social Athletics Club. 'Ping Pong' is showing at London's Rich Mix on 4-5 August 2012, then heads to Scotland and Wales mid-August. For more information visit www.pingpongfilm.co.uk

A ticket into the award-winning velodrome in the Olympic park may be one of the hottest in town this summer, but those without can still watch Olympic cyclists. The Olympic road races run from The Mall at 10am on 28-29 August, heading out through Kingston to Box Hill and back; while the road-cycling time trials start from Hampton Court Palace in Richmond on 1 August.

With transport issues reaching Twenty Twelve-style ridiculousness during the Games, cycling has become one of the fastest, not to mention most pleasant, ways to get around, especially in the east of the city. And so, inevitably, from necessity to alternative happenings: the Tweed Run, naked bike ride, and bicycle polo.

Played in the 1908 London Olympics, bike polo is having a come-back. It is played mainly on fixed-gears and involves a certain amount of skill; basically whacking the ball into the net with a mallet, without putting a foot on the floor. But anyone can join the party; every Sunday on Brick Lane, Wednesday in Vauxhall, and Thursday in Dalston.

Fast pedallers may be more interested in Rollapaluza: speed cycling on exercise bikes. It can take place anywhere, from the upstairs room of an East End pub to the park, to a suitably alternative soundtrack, and a baying crowd.

And in Soho, the Rapha Cycle Club has opened as a place to have a beer and food with fellow bike nuts and watch racing, from the Tour de France to Olympic road racing, on the big screen. Likewise on Old Street, the brilliantly named Look Mum No Hands! is a bar-café-cycle workshop, also with a big screen, which puts on regular cycling events. Riders and non-riders all welcome; Lycra is very much encouraged.

The craze for synchronised swimming has hit London ahead of this year's Olympic Games, even featuring in the June issue of Vogue, and now the public can show off their own ballet legs in the rooftop pool at The Berkeley.

Synchronised-swimming squad Aquabatix has teamed up with the Knightsbridge hotel to offer a 90-minute masterclass to guests and Londoners every Wednesday throughout July. Donning their most glamorous swimsuits, plus nose clips and a Berkeley swimming cap, students will take to the water gracefully (or not so gracefully, depending on your experience) after watching a routine performed by the squad.

It's not as easy as it looks in the Olympics - these are, after all, professional athletes with core muscles beyond belief. However, the professionals will endeavour to instruct guests in the intricacies of sculling artistically and the 'egg-beater' - where one treads water with the legs only, keeping the top half of the body out of the water. At the end of the class, the group of eight will, hopefully, perform in harmony to music.

Those who prefer to watch can see Aquabatix members Jenna Randall and Olivia Federici competing as a duo at the Olympic Games this summer. Or you could go all out and hire the troupe for your own private party - as David Walliams and Lara Stone did, who had them perform to Frank Sinatra's Come Fly With Me at their wedding party on the rooftop at Shoreditch House.

Ninety-minute classes run 6pm-7.30pm on 4, 11, 18 and 25 July 2012, and cost £125 per person. To book contact The Berkeley (0808 238 0245; www.the-berkeley.co.uk). For more information on Aquabatix, visit www.aquabatix.com

The pop-up is a recreation of the department store's original mini-golf course that was set up on the roof in the 1930s (pictured). This time around it's even crazier: every hole on the nine-hole course represents an iconic London landmark, as it would look if it were made of cake.

There's a peachy-pink Big Ben at hole number 2, complete with piped fondant 'icing'; a buffet of jelly St Paul's Cathedrals on cake-stands at number 5. Hole 4 is Tower Bridge, half-raised, over a pool with stepping-stones so you can fish out your ball if you land it in the water. Most marvellous of all is the rotating Gherkin in lilac at number 9.

The patisserie-themed landmarks have been designed by Bompas & Parr - jelly artists extraordinaire, hence the sweet theme. Even the golf balls are candy-coloured, and the score-cards infused with scent of Bakewell tart.

The real thing is to be had at the Daylesford roof café next to the course, which serves afternoon tea, cakes and Pimm's. There are rustic wooden tables and chairs, apple trees and umbrellas to keep off too much sun or rain, and raised beds of strawberries and mint, rhubarb and lettuce; the whole affair has the feel of a lovely garden party. Good shot!

Round of golf, £6 per person. Afternoon tea, from £30.95 for two. Open from midday, every day, 31 May-2 September 2012. You can just turn up, but to avoid a queue, book ahead; for more info go to www.selfridges.com/bigbritishbang; to book a round of golf, go to www.jellymongers.co.uk

Like scaling Sydney Harbour Bridge or walking up the steps inside the Eiffel Tower, Up at the O2 is an new experience intended to let people interact with an iconic landmark. This time it is an open walkway, suspended above the O2, formerly the Millennium Dome.

Imagine the Millennium Bridge, without any handrails, curving steeply up at an angle of 30 degrees to the top of Nelson's Column, and you've got the idea. Up to 15 people at a time are each attached by a harness, so your hands are free (though it's a long way down if you drop your smartphone), to a latchway system in the middle of the 190-metre walkway stretched between the O2's distinctive yellow masts. It doesn't actually involve any skilled climbing at all, but it's an exhilarating ascent, nonetheless.

Opening 21 June 2012, it is designed by the original architects of the O2, Rogers Stirk Harbour + Partners. The walkway is made of the same springy tensile fabric as the Dome itself, and is open on either sides for uninterrupted views and vertiginous thrills.

At the summit, a viewing platform gives 360-degree views right across London, from the Olympic Park and the Thames Barrier to the Shard and beyond. After the climb, the moments at the top seem strangely peaceful, 53 metres up above the city.

Up at the O2 costs £22 for adults and children and lasts 90 minutes; to book contact www.upattheO2.co.uk

Put the shot against Aphrodite and Zeus at Supperclub in West London this summer. For three nights a week during the London Olympic Games, the club will be transformed into the Ancient Greek city of Olympia, and host a re-enactment of the very first opening ceremony of the Olympic Games.

Complete with flaming chariots, a human Mount Olympus, traditional Greek performances and costumes, the opening ceremony will be followed by a series of Ancient Olympic sporting events which clubbers are invited to join in.

The Olympic theme extends to the club's signature cocktail, the Crazy Horse, which will be served in miniature chariots; while themed dishes include Ancient Greek avgolemono and Olympic macaroons.

Olympia at Supperclub runs 27-28 July, 2-4 August and 9-11 August 2012. For more details or to book contact Supperclub, 12 Acklam Road, London W10 (020 8964 6600; www.supperclub.com)

A pop-up nightclub in central London is making a bold bid for the title of the capital's hottest nightspot during the Olympic fortnight. Legendary music producer Arthur Baker (New Order, Bruce Springsteen, Afrika Bambaataa) and party impresario Sara Blonstein (Cannes, MTV Awards, BAFTAs) are behind Nightgames - a private members club that will be open for just 12 nights.

The exact location of Nightgames is a secret, though the clamour for membership of the venue is likely to be more of a fraught experience than finding its West End location (clue: it is very near Selfridges on Oxford Street). Those that are lucky enough to get in are promised a ballroom mixed with a traditional members' club, complete with an exotic outside terrace.

The music will range from live big band performances to pure disco from the original DJs of New York's infamous Studio 54 nightclub. The organisers promise international music stars will also play at the venue, where all furniture has been replaced by beds and bespoke 'parlours' will spin off from the dance floor. The pop up will support the Teenage Cancer Trust and The Fashion Arts Foundation. The club is open from 26 July to 12 August, 9pm - 4am. Members only. For more details visit www.nightgames.co.uk